jobs: migrate related tag updates to ActiveJob.

app/jobs/update_related_tags_job.rb

@@ -0,0 +1,7 @@
+class UpdateRelatedTagsJob < ApplicationJob
+  queue_as :default
+
+  def perform(tag)
+    tag.update_related
+  end
+end

app/models/tag.rb

@@ -872,7 +872,7 @@ class Tag < ApplicationRecord
 
       if Cache.get("urt:#{key}").nil? && should_update_related?
         if post_count < COSINE_SIMILARITY_RELATED_TAG_THRESHOLD
-          delay(:queue => "default").update_related
+          UpdateRelatedTagsJob.perform_later(self)
         else
           sqs = SqsService.new(Danbooru.config.aws_sqs_reltagcalc_url)
           sqs.send_message("calculate #{name}")